


Frequency and Amplitude

by Owlship



Category: Bumblebee (2018), Transformers - All Media Types
Genre: Charlie Lives With The Autobots, F/M, Jealousy, Mutual Masturbation, Originally Posted on Tumblr, Other, Pining, Post-Canon, Pre-Relationship, Robot/Human Relationships, Sexual Interfacing, Vibrators, Voyeurism, bumblebee has a human kink tbh
Language: English
Status: Completed
Published: 2019-03-14
Updated: 2019-03-14
Packaged: 2019-11-18 02:22:38
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,025
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18111311
Author URL: https://archiveofourown.org/users/Owlship/pseuds/Owlship
Summary: Bumblebee might not be the most experienced Autobot in the galaxy, but even he knows how to spot a solo-interfacing device. His surprise is that it's in Charlie's possession, an unmistakable whine from an electric motor emanating from her room on the base on a near nightly basis





	Frequency and Amplitude

**Author's Note:**

> Written for a prompt on [tumblr](http://v8roadworrier.tumblr.com/post/183437729226/congratulations-on-900-followers-a-prompt-that)!

Bumblebee might not be the most experienced Autobot in the galaxy, but even he knows how to spot a solo-interfacing device. His surprise is that it's in Charlie's possession, an unmistakable whine from an electric motor emanating from her room on the base on a near nightly basis.

He's bunked next to her, of course, the better to keep her safe- but the walls are built with flimsy native materials, not good solid metal, and he can _hear_ not just the motor, but her reactions to it, her harsh breathing, her stifled moans, the sounds of slick lubrication.

At first he'd thought she was unwell the first time he heard her breathing go ragged, smelled the pheromones in her sweat. He'd nearly burst through into her room, sure she was malfunctioning- but then he'd heard her plead "just a little more, come on, that's it" and he'd realized what he was overhearing.

The shock had riveted him to the spot and he'd listened as she overloaded once, twice, three times before finally shutting off the motor she was using on herself.

Bumblebee had sat there crouched on the other side of the wall, practically vibrating himself with the urge to reach out to her, to at least indulge in manually interfacing himself and take away the ache.

He'd refrained, barely, and that set up a pattern that punctuates the night cycle. Charlie bids him goodnight with a hug and sometimes- his antennae twitch at the memory- even putting what humans call a 'kiss' on his face, her lips soft against his metal. Then she putters around the room for a little while, rustling fabric and sometimes singing to herself, and more nights than not if he doesn't force himself to sleep first, there will be the sound of that blasted little motor starting up.

Bee doesn't want to listen in, doesn't want to spy on her. If this were Cybertron there's no way he'd be able to hear her in the adjacent room. But this is Earth, and she doesn't seem to care that he can clearly hear her, smell her, feel the subtle vibrations of her shifting weight on the floor.

Tonight she's particularly vocal, her voice muffled like she's holding her hand against her mouth, not firmly enough to fully stifle the moans she's letting out.

He's stopped trying to force his spike to stay dormant when he hears her; it's less uncomfortable to let it extend, even if he then has to contend with the urge to touch himself.

Bumblebee wonders what she looks like when she interfaces with herself; he knows that her clothes can be removed, has seen pictures of 'naked' humans enough to have a basic understanding of what their bodies look like underneath. But he's never seen Charlie like that, her soft, smooth skin, the little tufts of hair that some humans have at their joints.

He wonders if she has an interfacing port like female Autobots do, if that's what she's touching with the motorized device, wonders what it looks like, feels like.

He has to pay attention to suppressing his radio on nights like this; it's become second nature to use it to vocalize, and Bumblebee sometimes slips up and plays bits of sound without meaning to. Alerting Charlie to the fact that he can hear through the thin walls means she'll probably stop, and he doesn't want that.

He hears her moan, her breathing frantic as she approaches overload, the motor increasing its pitch as she turns up its power.

He loses the battle with himself tonight, his hand creeping down to his aching spike, wrapping it loosely in a fist. He should get lubrication for this, but that would mean getting up and moving to the other side of the room, and he doesn't want to miss hearing anything of what Charlie is doing to herself.

Bee closes his eyes, entire body quivering and buzzing in a way he can't stop when he hears her overload with a not-muffled-enough cry.

He lets himself imagine her, how she must look in the pile of fabrics she sleeps on, her bare skin on display, so different from a Cybertronian. His hand strokes up and down his spike slowly, hoping the rasp of metal-on-metal isn't as loud as it sounds to him.

Would she even look at him, he wonders? Humans use mechanical objects for all sorts of things, interfacing included, but that doesn't mean she'd be willing or able to accept him as a partner. He'd be good to her, though; from what he can tell, the motor she uses to interface has a limited range of power and primitive functions.

He'd do better for her without even _trying_ , Bumblebee thinks dismissively.

He pictures it as he hears her start up again. How he'd touch her carefully, stroke her soft organic parts, make his fingers vibrate at any frequency she wants until she's begging him to interface properly, his spike sliding inside her port, pushing her to overload again and again.

Through the wall between their rooms he hears Charlie shout out, a dull thump of her flesh hitting something solid. He strokes his spike quickly, increasing the pressure of his fingers, feeling himself buzzing with vibrations in his eagerness.

His control slips and his radio lets out a burst of static, and Bumblebee freezes in place.

But Charlie only whimpers and keeps going, and after a moment, he picks up his movements again as well.

He's sloppier about it now, unable to fully suppress the buzzing noises his mechanics are making as he approaches overload.

"Ah!" Charlie gasps, and then- "Bee!"

And Bumblebee is overloading violently, processors shutting down as the energy of his Spark surges, nerves crackling.

When he comes back online all is silent, save for the faint sound of Charlie's breathing in the next room.

He rocks back away from the wall, unsure of what came over him, unsure if she heard him, unsure if _he_ heard _her_ correctly. Did she really say his name? Or was it just his aural inputs scrambling a more common sound, a product of wishful thinking.


End file.
